RESUMO
BACKGROUND: Odontogenic cysts and tumors exhibit varying degrees of aggressiveness in their biological behavior. Odontogenic keratocyst (OKC), dentigerous cyst (DC), ameloblastoma are most common odontogenic cysts and tumors to occur in the oral cavity. Myofibroblasts (MFs) in the connective tissue stroma participate in the matrix degradation process by secreting matrix metalloproteinase 2, transforming growth factor beta1 and may contribute to variation in their biological behavior. Its activity is identified by alpha-smooth muscle actin (α-SMA) marker. With this background, the present study aims to evaluate the frequency of MFs using α-SMA to determine the biological behavior of OKC, DC, and different clinical variants of ameloblastoma. MATERIALS AND METHODS: A retrospective study was carried out with total of 60 samples which include 10 cases each of OKC, DC, 30 cases of different clinical variants of ameloblastomas and 10 normal mucosa taken as controls. All are stained immunohistochemically using α-SMA and were analyzed for the same. Comparison between more than 2 groups done by one way analysis of variance test with the level of significance of P ≤ 0.0001, i.e., <0.05. RESULTS: Statistically significant difference in the mean number of MFs observed between certain groups, with higher mean number in solid ameloblastoma (SA) (32.45) followed by OKC (28.79), unicystic ameloblastoma (24.53), desmoplastic ameloblastoma (7.44), and DC (1.72). CONCLUSION: Higher frequency of MFs noticed in SA, OKC which are key cells for connective tissue remodeling by interacting with epithelial cells and other connective tissue cells to facilitate progression of cysts and tumors thereby contributing to their biological behavior.
RESUMO
CONTEXT: Fire investigation is the multidisciplinary basis of the exploration, which involves investigations concerning the origin of fire, its cause as well as the identification of victims. At times, victim identification in fire disasters becomes nearly impossible owing to complete destruction of soft tissues. In such circumstances, teeth may prove to be of value since they are extremely hard. A precise understanding of physical and histological changes in teeth subjected to high temperature can provide valuable clues in fire and crime investigations, when dental evidence remains. AIM: The main aim and objective of the study was to investigate structural damage in freshly extracted teeth to heating, at different temperatures for a certain length of time in the laboratory. SETTINGS AND DESIGN: Fifty-four freshly extracted teeth of different age groups had been subjected to different temperatures for a period of 15 minutes in the laboratory furnace. Physical and microscopic findings were correlated to the temperature. MATERIALS AND METHODS: Freshly extracted 54 permanent teeth of different age groups were collected and were subjected to temperatures of 100°C, 300°C, and 600°C. Teeth were then examined for any physical changes such as change in color, texture, or morphology that occurred. Then the teeth were subjected for decalcification following which the tissues were kept for routine processing and were embedded in paraffin wax. Sections of 4 µm thickness were made and stained in hematoxylin and eosin (H and E) to correlate the microscopic findings to the temperature. STATISTICAL ANALYSIS: Physical and microscopic findings were correlated to the temperature. RESULTS: Microscopic examination revealed definite histological patterns, which were explicitly seen at a particular temperature. The samples showed cracks and charring of the tooth structure with microscopic findings such as widening of dentinal tubules and altered histological staining. CONCLUSION: Evaluation of incinerated dental remains may provide additional forensic investigative avenues in victim identification because of the consistency of morphological changes, the histological patterns at temperatures that are commonly encountered in common domestic fires.
